Atmospheric drum drier



April 13, 1943. 'c. o. LAVETT 2,316,176

ATMOSPHERIC DRUM DRIER Filed Aug. 1, 1940 2' Sheets-Sheet 1 INVENTOR A r-i113, 1943; C,O.-LAVETT '2 ,3 16,l76

ATMOSPHERIC DRUM DRIER 7 Filed Aug. 1,1940 -2 Sheets-Sheet 2" r ATTORNEYS buckle or deflect. l I

Patented Apr. 13, 1943 2,316,176 ATMOSPHERIC DRUM DRIER Charles 0. Lavett, Buffalo, N. Y., assignor to Butfalo Foundry & Machine 00., Buffalo, N. Y;, a

. corporation ofNew York Application August 1, 1940, Serial N... 349,191

12 Claims. "(01. 159-11) This invention relates to an atmospheric drum drier which is provided with two rotary opposed drumsadapted to receive between them the material to be dried, and more particularly to a drier of this character having end boards arl ranged at opposite ends of the space between the heating surface to a certain extent. The

these drums for the purpose of forming with the y 1 upper opposing surfaces of these drums a feed chamber from which this material is supplied to the drums.

i With drum driers of this type the thickness of thecoating adhering to the drums is usually controlled by adjusting the .spacing between the drums, this usually being done while the drums are in operation. It has been customary heretofore to construct theend boards of wood although in some cases materials, such as Bakelite, have been employed; Such end boards made of wood or Bakelite are bolted to a heavy steel or cast iron backing plate to form a unitary struc ture.- Thebacking plate to which the wood or Bakelite is bolted has been necessarily heavy as the rigidity of the end board has been considered unimportant factonit being necessary to apply .suflicient pressure to the plate to provide a tight sealflbetweenthe drums and the end board. Fur: ther, end boards so constructed are required to :be of such thickness that the end boardswill not ,In adjusting the space between the drums it frequently happens that the drums are not in exact alignment at both ends and with rigid end boards constructed as above the resulting improper fit resultsin leakage of the liquid. Since wood or Bakelite end boards attached to a rigid metal plate are not freeto flex so as to fit the ends of the drum in case of misalignment and as the rigid metal plates are not free to expand andcontract with the .wood due to alternate wetting, heating, cooling and drying, end boards constructed as above have a tendency to bulge, crack, check and warp, particularly 'as it is necessary to take the boards out at nightfor .cleaning and to allow them to lie idle over night. With such wood or Bakelite end boards it has therefore been necessary each morning to allow a considerable timeto permit the end boards to wear in, and since the end boards do not properly lit the ends of the drums during such wearing in processes, leakage results. The liquid so'leaking first dries on the ends ofthe heated drums and later chars, this charred material in many in fstances becoming quitegritty and tending to wear the boards rapidly at the area contacted,

by the drums.

- steel orcast iron-plate, the unitary end board;-

If the leakage continues the material already deposited on thelends of the drums insulates material leaking out then does not dry completely, butbecomes gummy and discolored, the friction tending to force some-of this gummy substance to the cylindrical surface of the drum where upon reaching the knife or doctor blade it isremoved and thus mixes with the dry product taken from the drums. With such end boards it .will also be seen that the friction between the drums and the, end boards is very high, mainly due to the fact that an initial proper fit is not obtained and therefore excessive pressure has to a be applied to wearthe end boards in and prevent leakage as much as possible. This requires excessive power for driving the drums and also results in excessive wear on the drum bearings and the like.

With such end boards it is also necessary to allow for reasonable wear and hence end boards made of wood or Bakelite must be quite thick. As the wood or Bakelite is mounted on a heavy structure is necessarily heavy and awkward to handle, such end boards requiring two men to remove for cleaning and replacement even on a comparatively small size'drier. Extra care must also be taken to avoid damage to the drum surfaces when the boards are removed daily for cleaning. l V

It is the principal object of the invention to provide end boards which are made entirely of metal and are flexible so as to conform to the drums even when the drums are not properly aligned and thereby avoid the wearing in process accompanying wooden end boards with the resulting leakage and danger of contaminating the product as above described. I

Another objectof the invention is to provide a unitarymetal endboard which is not bolted or ing it against the drums. N

Another object of the invention is to provide rigidly held to any member employed for presssuch an end board which is not bolted to its support and is free to expand, contract or flex to fit the ends of the drums as may be required.

Another object of the invention is to provide an' end. board which is supported in proper-relation to the drums and which'ls pressed against the ends of the drums by independent members which exert the necessary pressure to form a leakproof seal. Such independent pressure, ex-

erting members can be applied in one or more places depending upon the size of the board, the rigidity of the board and other factors.

1 Another object of the invention is to provide one form of the invention in which the end board made of a sheet metal plate is backed by an independent reenforcing and pressure structure which is curved to conform to the circular contour of the drum, the reenforcing member bearing uniformly against the flat outer surface of the sheet metal plate so as to exert uniform pressure on the part of the sheet metal plate which is in contact with the drums.

Another aim of the invention is to provide such an end board in which the pressure members which hold the end boards against the drums are free to move within certain limits so as to permit the end boards to adjust themselves to the drum ends when the drums are not in perfect alignment.

Another purpose of the inveniton is to provide an end board which is made entirely of metal and light in weight and can be easily removed and replaced by one man.

Another object of the invention is to provide such an end board which is so mounted that the means for exerting pressure upon it are independent ofv the end board and it is necessary to remove only the end board for cleaning purposes.

Another purpose of the invention is to provide an end board constructed entirely of metal wherein the end board has sufficient flexibility to adapt itself to the drum ends and hence requires less pressure to provide an adequate seal and reduces the friction between the drums and the end boards and the power requirements for driving the drums.

Another object of the invention is to provide a board which is low in cost and can be made of any suitable sheet metal such as stainless steel, Monel metal, nickel, copper, steel, aluminum, laminated or unlaminated plastics and so forth; which will stand up under conditions of severe and constant use; which is easily kept in an absolutely sanitary-condition; which reduces material losses and the danger of contaminating the dry product and which can readily be replaced without elaborate wearing in processes.

In the accompanying drawings:

Fig. 1 is a fragmentary, vertical, transverse section of a double or two drum atmospheric dryer equipped with one form of end board and means for mounting the same embodying this invention, this section being taken on line i--i, Fig. 2.

Fig. 2 is a top plan view of the same.

Fig. 3 is a vertical, longitudina1 section, taken on line 3-3, Fig. 1.

Fig. 4 is a vertical transverse section, taken on line 4-4, Fig. 3.

Fig. 5 is a fragmentary top plan view of the end boards shown in Figs. 1-4 and showing the manner in which a notch is provided for greater flexibility.

Fig. 6 is a fragmentary view similar to Fig. 3 and showing a modified form of my invention.

Fig. '2 is a view similar to Fig. 1 showing a further modified form of the invention, this section being taken on line 1-1, Fig. 8.

Fig. 8 is a view similar to Fig. 2 showing the modified form of the invention illustrated in Fig. 7.

Figs. 9 and 10 are fragmentary sections, taken on the correspondingly numbered lines of Fig. '7.

In the following description similar characters of reference indicate like parts in the several figures of the drawings:

iii

aeiaive This invention is applicable to double drum driers which may be of various forms as to the details of construction and the drawings therefore only disclose such parts of a double drum drier which are necessary for the purpose of illustrating those features of such a drier which cooperate with end boards embodying the present invention. As there shown this drier comprises two cylindrical drums 5, 5 which have their axes arranged horizontal and parallel and their opposing cylindrical surfaces close together so as tqform a downwardly converging space. The main frame of the drying apparatus includes an upright standard at each of the corresponding ends of the drums, one of these being shown at 5 in Fig. 3, these drums being provided with horizontal trunnions i at each of their ends which are journaled in suitable bearings on the adjacent standard 5 of the main frame.

The material to be dried such, for example, as milk, may be fed into the feed chamber or space between the two drums by any suitable means and the rotation of the drums for bringing the peripheral parts of the same successively into contact with the material located between the upper opposing parts thereof may also be effected in various ways. The drums are heated internally and during their rotation some of the material to be dried adheres to the opposing upper peripheral parts thereof and is carried circumferentially thereon a suificient distance to dry this material after which the dried material is removed from the periphery of the drums by knives and then carried away in a manner well known inthis art.

The numeral 8 represents two splash shields or side boards which are arranged lengthwise above the upper part of the drum and extend at their ends slightly beyond the corresponding ends of the drums. These side boards prevent the material from splashing over the upper parts of the drums and are supported by the end boards embodying my invention. These end boards are each made of a plate of sheet material Q, such as sheet steel, copper, aluminum, Monel metal, nickel, stainless steel, or plastics. These plates or sheets 9 are pressed against the opposite ends of the drums 5 so as to form the space or valley between the drums which contains the material to be dried by the drums. Each of these end boards so made of sheet material is constructed to form an upper wide part iii having vertical edges ii and a narrow lower part it having its opposite edges is converging downwardly from the lower ends of the vertical edges ii to a point somewhat below the axes of the drums. These downwardly converging edges it of the lower narrow part 52 of the end board are preferably curved concentric with the axes of the drums and each of these curved edges is pressed fiatwise against the respective end of the corresponding drum by a separate backing and reenforcing structure, as hereinafter described, In order to stifien the vertical edges of the upper part iii of the plate 9 and also to provide an extended face for supporting the splash shields or side boards 8, these edges are preferably flanged, as indicated at i i, the side boards 8 being secured against the outer faces of these flanges it in any suitable manner (not shown).

The upper horizontal edge of the plate s is also similarly flanged, as indicated at 55, but this flange is preferably hook-shaped in cross section, its outer edge being bent downwardly for this purpose. This flange i5 can also be notched at its center, as indicated at Hi5, so as to permit manner. ing rods 20 extends into one of the socket lugs these curved bars 11, as shown in Fig. 1. connection between the screws 25 and 21 and the cross bars 23 and 24 is sufiiciently loose so that the plate 9 to freely flex along a vertical central axis and the ends of the flanges l4 and I5 are preferably not'connected to one another, thereby to provide greater flexibility for the plate 9.

Each plate 9, as above described, is a separate removable structure which forms the end board for the drier and is held in place by a supporting structure which in turn is carried by the frame of the drier, this supporting structure being yieldingly pressed against the corresponding plate 9 so as to insure a tight seal between each plate 9 and the corresponding ends of the drums.

As shown in Fig. 1, each of these supporting structures includes a vertical bar l6 each of which is preferably welded to a lower curving bar 11, the horizontal flange ii of the sheet or plate 9 hooking over the upper ends of the bars plate 9 to flex along its central vertical axis, this flexing being further insured by the provision of i the notch H5 in the flange I5, as previously described.

Secured to each of the curving bars I! is a supporting lug l8 each of which is formed to provide a socket and is preferably' constructed from a. strap of metal which is bent into the shape of an inverted U and secured at the lower ends of its legs to the upper part of the bar H. by welding, as indicated at l9. Each socket lug I8 is only connected with the adjacent bar l1 and is not connected withthe adjacent part of the plate 9. These supporting lugs are carried by short rods 20, each of which is supported in a socket 2| formed in the frame 6 and held in position by a set screw 22 or in any other suitable The free end of these short support- IB so that the bars l6 and I! are hung upon these rods and the plate 9 in turn hung on these bars, the rods 20 thereby serving as the support for each end board but permitting a limited movement of the bars l6 and I! so as to permit the end boards to adapt themselves to the ends of the drums. r

Each of the end board plates 9 is pressed against the corresponding ends of the drumsby spring pressed retaining devices which permit a limited movement of the end board. For this purpose the upper ends of each pair of bars I! are tied together by an upper cross bar 23 and the lower ends of the curving bars I! of each end board are connected by a lower horizontal bar 24 which is comparatively short. The upper abutment bar 23 issecured at its opposite ends by means of screws 25 to lugs 26 projecting outwardly from the upper parts of the curved bars I! and each lower abutment bar is secured at its opposite ends by means of screws 21 to lugs 28 which project outwardly from the lower parts of The the curved bars H are free to move, within certain limits, relative to the cross bars 23 and 24 and therebyadapt themselves to the ends of the drums inexerting pressure against the plate 9.

In the form of the invention shown in Figs.

cured to the frame 6.

end with a fork 3|, each fork straddling one of the abutment bars 23, 24 at the center of the abutment bar. Within the tubular. housing 29 the thrust rod is provided with an outwardly facing shoulder which is preferably formed by means of a collar 32 secured to this rod and at its outer end the rod isprovided with a stop collar 33. Surrounding the outer part of the thrust rod and extending partway into the outer end of the housing tube 29 is a tubular adjusting screw 34 which is turned by means of a hand wheel 35 secured at its outer end. A compression spring '36 of helical form is shown as surrounding the thrust rod 30 within the tubular housing and interposed between the collar 32fand the end of the tubular adjusting screw 34, as shown in Fig. 3. The central part of the tubular adjusting screw 34 engages with the threaded, opening 31 formed in a nut 38 which is demountablyseturning the screws 34 the pressure upon the upper and lower springs 36 can be varied to produce the desired pressure exerted by the thrust rod 30 against the cross bars23 and 24. This adjustable spring pressure is in turn applied to the curved bars I! and thereby yieldingly urges the curved edges I3 of the plate 9 into engagement with the ends of the drums. By this means a plate joint can be produced between the end boards 9 and the ends of the drums without creating a condition of undue friction.

Each of the nuts 38is preferably made quickly I detachable from the frame so that each of the spring loaded retaining devices can be easily and quickly removed from the frame and disengaged from the end board so thatthe end board can be quickly removed from the drier when itis desired to clean or service the apparatus. The quick detachable means for the nuts 38 include two bolts or studs secured to the outer side of the frame standard Bon opposite sides of each tube 29 and eachstud having an enlarged head 39 and a reduced neck 40. Each nut 38 is formed to provide twohooks 4| at opposite sides, the nut being turnable to move thes hooks into and out of engagement with the necks of the studs. As illustrated in Figs. 2 and 4, the nut has been turned so that its hooks 4| engage the necks 40 of the studs so that the nut is held against axial movement and hence causes the screw 34, upon being rotated, to exert or relieve pressure upon the spring 36 to the desired extent. Upon turning each nut 38 to disengage its hooks from the studs 39 and 49, this nutwill be released and permit the attached retaining device to be withdrawn outwardly through the tube 29 and v disengaged from the corresponding cross bar 23 or 24. Upon soreleasing the pressure ex.- erted against the end boards 9 it will be seen that the sheet metal end boards can readily be lifted free from the supporting bars l6, l1 and removed for the purpose of cleaning or replace ment. I

Inthe rform of the invention shown in Fig. 6 only one adjusting device'pis'provided for each end board. To this end a vertical bar is provided, this bar having a lip 46 at its upper end which engages over the cross bar 23 and having a It will be seen that upon numerals have been applied.

. position shown in Fig. 1.

lip 41 at its lower end which engages under the lower cross bar 24. At its center the vertical bar 45 is pressed toward the drums by a spring loaded adjusting device which is identical with the two adjusting devices used in the form of the invention shown in Figs. 1-5. Inasmuch as the construction of this adjusting device is identical with those shown in Figs. l-5, the same reference that in this form of the invention one adjusting screw, is eliminated and at the same time the pressure of the single adjusting screw is applied centrally of the'end board and uniformly distributed to the extremities of the curved bar I! through the medium rof the vertical bar 45 and the cross 'bars 23 and 24.

In applying the end boards to the drum drier,

' the hand wheels 35 are turned so that the thrust rods 30, cross bars 23 and 24 and the vertical and curved bars l6 and I! can be backed up sufficiently to slide the plates 9 of sheet material between the bars l6, l1 and the adjacent parts of the ends of the drums. In so placing the end plates 9 in position the hook-shaped upper flange of the plates 9 is caught over the upper edges of the bars I 6 so that the plates hang from the upper ends of these bars IS in the Since the bars l6 and H are directl-ysupported through the lugs l8 on the'short rods it will be seen that the 1 plate 9 is held in proper relation to the space or valley between the drums. The operator then turns the hand wheel to exert pressure against the compression springs 36, the tubular screw 34 of the hand wheels 35 being mounted in the nuts 38 for this purpose. springs 36 is in turn transmitted to the thrust rods30 and through the forks 3| to the centers of the cross bars 23 and 24. The pressure against these cross bars is in turn transmitted to the upand I5, and since the lugs H! are loosely hung upon the ends of the short rods 20 to permit a It will be seen,

of backing up the screws 34 the same release of spring pressure can be obtained by. releasing the nuts 38 from the studs which hold them against axial movement.

In the form of the invention illustrated in Figs. 7-10 the construction of the drying drums and thesupporting Structure for the end boards is identical to the construction illustrated in Figs. 1-5 and hence the same reference numerals have been applied. The essential difference between the end board illustrated in Figs. 7-10 and the end board illustrated inFigs. 1'-5 is that the bars which reenforce the vertical and lower curving edges .of the sheet metal plate of the end board are disposed between this sheet metal plate plate are preferably curved concentric with the The pressure of the limited movement of the bars I! transversely of I the axes of the drums, and since the screws 25 and 21 are connected to the lu s 26 and 28 in such manner as to permit a limited amount of movement between the cross bars 23 and 24 and the curved bars I1, it will be seen that the plate 9 can readily adapt itself to variations in the ends of the drums, the entirestructure being sufficiently flexible to permit of such adaptation. The plate 9 is therefore yieldingly held against the end of each of the drums to provide an immediate effective seal without undue friction and without danger of a part of the material being dried becoming burnt and discolored so as to impair the final dried product.

To remove the end boards it is merely necessary to back off the screws 34 and relieve the spring pressure against the cross bars 23 and 24.

Upon release of such pressure the plates 91 can be 1ifted upwardly from engagement with the upper ends of the bars l6 and removed from the drier. This can readily be accomplished by one operator. It will also be seen that instead axes of the drums. To stiffen the vertical edges of the upper part 59 of the plate 49, and also to provide an. extended face for supporting the splash shields or side boards 8, these edges are preferably flanged, as indicated at 54, the side boards 8 being secured against the outer faces of these flanges 54 in any suitable manner (not shown). The upper horizontal edge of the plate 49 is also shown as similarly flanged, as indicated at 55, butthis flange is preferably hook-shaped in crosssection, its outer end being bent down wardly for this purpose.

Interposed between the sheet metal plate 49 and the ends of the drums 5 is a sealing bar 60 each of these sealing bars conforming to the side edges of the plate and thereby having an upstanding straight part 6| extending along the corresponding vertical edge 5| of the plate and a lower arcuate part 62 extending along the corresponding curved edge 53 of the plate. These ,ba-rs can be secured to the plate 49 in any suitable manner..as by screws 63, and the lower opposing ends of these bars are provided with machined contacting faces 64. These lower contacting ends of these bars 60 arenot secured together, however, except through their mutual connection with the plate 49 itself, and hence these bars do not in any way interfere with the free flexing of the plate 49 about its central vertical axis aspreviously described.

To support th plate 49 on the rods 20 of the supporting structure, a pair of plates 65 are shown as welded on the outer face and at the opposite sides of the plate 49 and each being formed to provide a saddle-shaped extension 66 which fltsover and rests upon the corresponding supporting rod 20 of the supporting structure. Similarly, to connect the opposite ends of the upper cross bar 23 with opposite sides of the plate 49 in rear of the upper ends of the curved parts 62 of the sealing bars 69, angle pieces 61 are secured to the rear face of the plate 49 by two of the screws 63, these angle pieces forming ears to which the ends of the upper cross bar 23 are pivotally secured by the screws 25. -At its extreme lower end, a pair of angle pieces 68 are secured to the plate 49 in rear of the bars 60, these angle pieces being pivotally connected by the screws 21 to the ends of I carried by the supporting struct i t I the rods Zlland pressed atfouripoints against'the j" ends of the drums by. thebars 2? and fl linjthe .5

" side edges of the plate 49 are securedto the nn ri cleaning-is required. l

readily adapt itself to minor irregularities all metal construction the' disadvantag'e-oi, warp= Y 7 material without renderinglit prohibitively expent of the thrust rods 30- andthese cross bars 23 and I claim as my invention:

'end of the space between the opposing sides of jacent the opposite side edges of said sheet, means ing said end board into sealing engagement with dried betweenthem, and means fo closing ch 7 end or the space between the, opposing-sides" oi. said drumsg including-an end board; comprising asheet of flexible materialaand rigid reen'forcingx V g bars arranged alongthe opposite side edges orqsaid sheet and separate from ea'chnther at'th'e central.v s'verticalmaaxis {of jsaid sheet to, provide "flexibility p insaid endxboard-along said fcentral 'ertical axis; I anda pressure'idejvice carried by saidfra'ni d raceof the plate to engage thedrum 5 instead i ,0! being merely pressed against thefoutefriace of the plate 4 9 asin Figs. 1-5.; Itwillthereiore L be seen that lnthe form of the inventionillus-jft a a aaiaize t the lower cross barf of the presser mechanism It will be seen that-the plate :49 is suppq lit dby i same manner as in the form otllthefin vention shown in Figs. 1-5, the only vessential difierence being that the side bars 50 whichreenforce the 1 end board into ::,S,ea1in'g, engagement {with jacent redgesof-said'druins:m n g g 3.-:An :=atni'osphetic drier jcomprising a f tratedinFigs. 7 10, these side bajrs ifiqliormlthe two rotary idrums' arrangedfsideby side} sealing surfaces between the endtboard and'the fframethd-adapted toreceivethe materia L drums and are removed withthefplate dii'whendrie betweenwtheni and irieansforicl ing; a'cl'r r endrot-thespacebetweerrthe opposing'isideso aid From the foregoing it will beseen thatth drums,-1includingamend-boardcompris ent invention provides a very simpleigendfijboa bf flexible; material;'\ the "lower flportioh V which is light in weight and canine easily remove'd 2o i side edgeoi whichiis substantiailycondentrie from and appliedto a drierhy oneoperator with a minimum of effort. It willfurther beseen tha by the flexible form. of "the sheet metal usedjas 1 the end board and by the flexibility provided-xi i the support for this flexible backingplate and 'in, thespring devices forholding the plate in engagement with the ends of thevdrums, theplate'ca'n --the jaljaxis; anda pressure idevice; carried rame;5and {urging each lof saidr reeniotc centric hedges oims'aid; 'endboard into s'e'ali' gagement wit ends of the drums and hence providean imm ateeiiectiVeseaI in contradistinction to;the weare I ing in processes required with woo d 'or fiakelite taryydi' umsxarr v m; y endboards/[It will be i'urther seentjthat y-Lthe" frame and adapt i leceiye j thematerialt be g g g n .-dried ibe"tweenjtiiem; an'djmeanqfor'closin each ingand swelling in the end boards iseliminated end otuthespace betweenk'the op'posing' sldesj "oi and that by the use of metal the irictionlibetweeny'ss saiddrumsjiiricluding anfiend board symmetrical the end board and the drums is reduced; thereby ab0ut:=its1entral vertical axis and comprisingsa 1 reducing wear as well as reducing the power I sheetlot rflexible .materia1}having an upper' irec-j quirements for-turning the drums. Itwill alsobe tangularpart1and-aglowerpart each sideledse Tot l seen that byproviding an'end board of simple whichilowe'rpart issubstantially concentriclwithfl, i construction, the endnboard can be veryea'sily 4 thevcorre'sponding drum andfrigid reenforcirigg kept me completely clean and sanitary candl barsha'ving lower curvedijparts' arranged along tion, and it will further be noted thatsuch an end i theyconeentricfledges ofsaid sheefland upstand board-can be made of stainless steel or other sheet ingrvertic'al' parts-arrangedalong th'e side" edges l l sive. ii i i y r l reenforcingabars beingfiseparate fromeach 'other While I have shown a specific embodimentrof i at said central verticalaxisof-said sheetft'okprbimyinvention it will be understoodthatthe em-t videiiexibility in"saidend' boardalong said'cen -j in bodiment shown and described can :be varied, traliverticalaxis;and a pfiessuredeyice carried widely without departing from the spirit of my in-i 'said framei and'f urgiii' each "of {said reen forcedf vention. Forexample, the cross bars 23 and 24 5o concentric;edges":ofpsaid en'd board into sealing I can be made of spring steelso as to eliminate the i engagement with ,the vgadjacentf edges 'ojfysaid necessitytor the springs 36 and means other than :driimsl the forks 3| can be employed between the ends 5.An atmospheric drier, comprising a frame,

. two rotary drums arranged side by side-onsaid 24. 1 The invention is therefore to be accorded the 5 frame and: adapted to receivethe material to be full range of equivalents comprehended by the accompanying claims.

driedbetween them, and means'forclosing each, end of the space between the opposing sidesof said drums, including an end board comprising a 4 1. An atmospheric drier, comprising a frame, sheetof flexible materialand reenforcing bars setwo rotary. drums arranged side by side on said cured to the inner face of said shee'tjaiong the frame and adapted to receive-thet material to be edges thereof,means forguidinglysupporting said driedbetween them, and means for closing each end board on said frame and a pressure device carriedby said frame and urging the reenforced said drums, including an end board comprising a edges of'said end board into sealing engagement i sheet of flexible material and reenforcing bars ad- 5 with the'ends ofsaid drums, f p

i p 6. An atmospheric drier, comprising aframe,

two rotary drums arranged side by side on said irame and a pressure device carried by said frame frame and adapted to receive the material to be r and pivotally connected with said reenforcing dried between them, and means for closing each bars at opposite sides of said end board and urg- 70. endof the space between the opposing sides '01 said drums including an end board'comprising] a sheet of fiexible material and reenforcingbars' bearing against the outer'face of said sheetalong the edges thereof and disconnected*therewithj meansflfor guidingly supportinglsaid end board for guidingly supporting said end board on said the adjacent ends of said drums. I I

2. An atmospheric drier, comprising a frame,

two rotary drums arranged side by side on said frame and adapted to receive the material to be on said'frame and a pressure device carried by said frame and connected with said reenforcing bars at alplurality of points and urging the re enforcediedgesof, said end board into sealing en agement with the ends 'oftsaid drums.

"T. An"atmospheric drier,comprising,a"frame,

f'two rotary'drums arranged side'by' side on'said frame andadaptedtoreceive'the material to'be gene of the space -betweenlthe opposing sides of tsaid drums including'an' endgboard comprising a sheet; of flexible material and reentorcing bars "acent the side-edges oilsaidsheet, means for em'ovably supporting); said end:bcard- 'onsaid frame and La ,pressure device 'iric'zluding a bar I j'ointedlyconnectinggther opposite reeniorced' side edges'bfsaid endlboa'rdand permitting saidreen orcedledgesof said end board to flex relative to gin. adapting themselves to fit the ad- 8; i arrangedlside by sidej'and' adaptedgto re} ons aid,iframe, and a structure'v for pressingsaid i an abutment member; and provided. with a shoulder,

- 'onfthe irarrle andftvhich receives said;rod-', screw having its edges engaging'corresponding ends of said drums, and means ,ior pressing said board I a ainst the endsof, said drums including an abutmient bar arranged across the outer side of the connected with the opposite, edges thereof, a thrust member connected with the-central part of i said abutment: bar and spring means interposed between said thrust rnember anfd vtl'iefr'arne and operating to ,press said thrust member against said abutment bar;

' dried between them, and means for closing each of"saidldrumsrandmeansfor urging. toward the adjacent ends of -said-l drums;- J atmospheric. drier. comprising two 'r'otary ceive etween themthe materialto be dried a onl which said drums arevj'ournaled, an end engaging corre'sponding 'end's "oifjsa'id; drums V eigtendingacross the space between, them, ean fo e isl pporting saidfend bcard' i (end board toward the. d ce e Isaiddmms lagjtubular screw which receives; saidirod a spring interposed betweenlsaidgshoulderflandsaid serew, L

ai -bracketmounted onthe frame and provided I t t .a threaded opening which{receives/said screwand, a tubular housing which-is mounted ay-'9; Anjatrnos'pheric, rier comprising a pair of I opposed rotary drums adapted to receivethe ma terial'to be dried, between them, an end board I endgboard and'having its 'opp'osite ends pivotally' 10. An atmospheric drier comprising parallel rotary drums having a downwardly converging space betweenthem for the reception of the material to be dried, an end board which extends across said space at corresponding ends of said 7 drums' ian'd" which has a wide upper part and a .narrowlower part, a comparatively long abut- I T ment bar pivotally connected at its opposite ends withthe outer side of the upper wide part of said board'a relatively short abutmentbarpivotally connected at its opposite ends with the outer side eluding an abutmentilmember associated withsa'id end, board a thrust-rod engagingsaid of the lower wide part of said board, upper'spring pressure means interposed" between the central part of saidupperjabutment bar and the frame,

and lower spring pressure means interposed betweenthe centralpart'of said lower abutment bar andthe frame; I p I friul l. An atmospheric drier comprisingv parallel rotary drums having a downwardly converging space between them for the reception of the mate- 'Igri'al' to be dried, an end board which extends across said space at corresponding ends of said drums and which has) a wide upper part and a narrow ower part, a comparatively long abutment bar "pivotally connected at its'oppositeends with the outer-side cf the upper wide part of said board,

a relatively' short abutment bar pivotally conne'cted'atits opposite ends with the outer side of the lower narrow part of said board, a vertical barwbearing against the central partsof said up- 7 per and lower-bars and adjustable spring pressure means bearing against the central part of said verticalgbari to hold said end board in tight enca ement vmh the ends of said drums.

12. An atmospheric dn'er, comprisinga frame,

two rotary; drums arranged side by side on said frame and adapted to receivethe material to be dried between them, and means for closing each 7 end of the space betweenthe opposing sides of said drums, including an end board comprising a sheet of flexible material and reenforcing bars adjacent the opposite side edges of said sheet,

. means for guidingly supporting said end board on said frame and a pressure device carried by said I frame and includinga member pivotally con- 2 nected with said'reenforcing bars at opposite sides of said end board, and means connected to the central part of said member vand urging said member toward the adjacent ends of said drums whereby said'end board is pressed into sealing engagement with the adjacent ends of said drums.

CHARLES o. LAVETT. 

